The use of high magnification optical microscopy has become an indispensable resource in the investigation of cellular organisms. Owing to their low endogenous absorbance and weak scattering properties over the visible optical spectrum, cells primarily affect the phase of optical waves traveling through them and thus appear semitransparent when imaged with standard bright field microscopes. This fact has inspired the utilization of phase to enhance contrast in cellular imaging (e.g., phase contrast and differential interference contrast microscopy) and quantify cellular structure Preza C et al, in Handbook of Biomedical Optics, D Boas, C Pitris and N Ramnujam eds, Taylor and Francis Books, London 2011, p 483; Shaked N T et al, Biomed Opt Express 1, 706 (2010); Wang Z et al, Opt Express 19, 19907 (2011); all of which are incorporated by reference herein). While the use of phase contrast and differential interference contrast microscopy in qualitative investigations of cellular morphology has become widespread, the use of quantitative phase retrieval methods and their connection to cellular refractive index and dry mass density (Barer R, Nature 172, 1097 (1953); incorporated by reference herein) remain confined to a handful of laboratories. This is a result of the restriction of phase and cellular mass determination to custom built instruments (Wang et al, 2011 supra and Charrire F et al, Opt Lett 31, 178 (2006) and Choi W et al, Nat Methods 4, 717 (2007); both of which are incorporated by reference herein), involved mathematical analysis (Klibanov M V et al, Inverse Probl 11, 1 (1995); incorporated by reference herein), and prohibitive sample perturbations (Barer, 1953 supra).